org.eclipse.jface.text.rules

Class FastPartitioner

java.lang.Object

org.eclipse.jface.text.rules.FastPartitioner

All Implemented Interfaces:

IDocumentPartitioner, IDocumentPartitionerExtension, IDocumentPartitionerExtension2, IDocumentPartitionerExtension3

public class FastPartitioner
extends Object
implements IDocumentPartitioner, IDocumentPartitionerExtension, IDocumentPartitionerExtension2, IDocumentPartitionerExtension3

A standard implementation of a document partitioner. It uses an IPartitionTokenScanner to scan the document and to determine the document's partitioning. The tokens returned by the scanner must return the partition type as their data. The partitioner remembers the document's partitions in the document itself rather than maintaining its own data structure.

To reduce array creations in IDocument.getPositions(String), the positions get cached. The cache is cleared after updating the positions in documentChanged2(DocumentEvent). Subclasses need to call clearPositionCache() after modifying the partitioner's positions. The cached positions may be accessed through getPositions().

Since:

3.1

See Also:

IPartitionTokenScanner

Field Summary

Fields

Modifier and Type	Field and Description
protected int	fDeleteOffset The offset at which a partition has been deleted
protected IDocument	fDocument The partitioner's document
protected int	fEndOffset The offset at which the last changed partition ends
protected String[]	fLegalContentTypes The legal content types of this partitioner
protected DefaultPositionUpdater	fPositionUpdater The position updater used to for the default updating of partitions
protected int	fPreviousDocumentLength The document length before a document change occurred
protected IPartitionTokenScanner	fScanner The partitioner's scanner
protected int	fStartOffset The offset at which the first changed partition starts

Constructor Summary

Constructors

Constructor and Description
FastPartitioner(IPartitionTokenScanner scanner, String[] legalContentTypes) Creates a new partitioner that uses the given scanner and may return partitions of the given legal content types.

Method Summary

Modifier and Type	Method and Description
protected void	checkInitialization() Calls initialize() if the receiver is not yet initialized.
protected void	clearPositionCache() Clears the position cache.
ITypedRegion[]	computePartitioning(int offset, int length) Returns the partitioning of the given range of the connected document.
ITypedRegion[]	computePartitioning(int offset, int length, boolean includeZeroLengthPartitions) Returns the partitioning of the given range of the connected document.
void	connect(IDocument document) Connects the partitioner to a document.
void	connect(IDocument document, boolean delayInitialization) Connects this partitioner to a document.
void	disconnect() Disconnects the partitioner from the document it is connected to.
void	documentAboutToBeChanged(DocumentEvent e) Informs about a forthcoming document change.
boolean	documentChanged(DocumentEvent e) The document has been changed.
IRegion	documentChanged2(DocumentEvent e) The document has been changed.
protected TypedPosition	findClosestPosition(int offset) Returns the position in the partitoner's position category which is close to the given offset.
protected void	flushRewriteSession() Flushes the active rewrite session.
DocumentRewriteSession	getActiveRewriteSession() Returns the active rewrite session of this document or null.
String	getContentType(int offset) Returns the content type of the partition containing the given offset in the connected document.
String	getContentType(int offset, boolean preferOpenPartitions) Returns the content type of the partition containing the given offset in the connected document.
String[]	getLegalContentTypes() Returns the set of all legal content types of this partitioner.
String[]	getManagingPositionCategories() Returns the position categories that this partitioners uses in order to manage the partitioning information of the documents.
ITypedRegion	getPartition(int offset) Returns the partition containing the given offset of the connected document.
ITypedRegion	getPartition(int offset, boolean preferOpenPartitions) Returns the partition containing the given offset of the connected document.
protected Position[]	getPositions() Returns the partitioners positions.
protected String	getTokenContentType(IToken token) Returns a content type encoded in the given token.
protected void	initialize() Performs the initial partitioning of the partitioner's document.
protected boolean	isSupportedContentType(String contentType) Returns whether the given type is one of the legal content types.
void	startRewriteSession(DocumentRewriteSession session) Tells the document partitioner that a rewrite session started.
void	stopRewriteSession(DocumentRewriteSession session) Tells the document partitioner that the rewrite session has finished.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

fScanner

protected final IPartitionTokenScanner fScanner

The partitioner's scanner

fLegalContentTypes

protected final String[] fLegalContentTypes

The legal content types of this partitioner

fDocument

protected IDocument fDocument

The partitioner's document

fPreviousDocumentLength

protected int fPreviousDocumentLength

The document length before a document change occurred

fPositionUpdater

protected final DefaultPositionUpdater fPositionUpdater

The position updater used to for the default updating of partitions

fStartOffset

protected int fStartOffset

The offset at which the first changed partition starts

fEndOffset

protected int fEndOffset

The offset at which the last changed partition ends

fDeleteOffset

protected int fDeleteOffset

The offset at which a partition has been deleted

Constructor Detail

FastPartitioner

public FastPartitioner(IPartitionTokenScanner scanner,
                       String[] legalContentTypes)

Creates a new partitioner that uses the given scanner and may return partitions of the given legal content types.

Parameters:

scanner - the scanner this partitioner is supposed to use

legalContentTypes - the legal content types of this partitioner

Method Detail

getManagingPositionCategories

public String[] getManagingPositionCategories()

Description copied from interface: IDocumentPartitionerExtension2

Returns the position categories that this partitioners uses in order to manage the partitioning information of the documents. Returns null if no position category is used.

Specified by:

getManagingPositionCategories in interface IDocumentPartitionerExtension2

Returns:

the position categories used to manage partitioning information or null

connect

public final void connect(IDocument document)

Description copied from interface: IDocumentPartitioner

Connects the partitioner to a document. Connect indicates the begin of the usage of the receiver as partitioner of the given document. Thus, resources the partitioner needs to be operational for this document should be allocated.

The caller of this method must ensure that this partitioner is also set as the document's document partitioner.

This method has been replaced with IDocumentPartitionerExtension3.connect(IDocument, boolean). Implementers should default a call connect(document) to connect(document, false) in order to sustain the same semantics.

Specified by:

connect in interface IDocumentPartitioner

Parameters:

document - the document to be connected to

connect

public void connect(IDocument document,
                    boolean delayInitialization)

Connects this partitioner to a document. Connect indicates the begin of the usage of the receiver as partitioner of the given document. Thus, resources the partitioner needs to be operational for this document should be allocated.

The caller of this method must ensure that this partitioner is also set as the document's document partitioner.

delayInitialization indicates whether the partitioner is allowed to delay it initial computation of the document's partitioning until it has to answer the first query. Replaces IDocumentPartitioner.connect(IDocument).

May be extended by subclasses.

Specified by:

connect in interface IDocumentPartitionerExtension3

Parameters:

document - the document to be connected to

delayInitialization - true if initialization can be delayed, false otherwise

checkInitialization

protected final void checkInitialization()

Calls initialize() if the receiver is not yet initialized.

initialize

protected void initialize()

Performs the initial partitioning of the partitioner's document.

May be extended by subclasses.

disconnect

public void disconnect()

Disconnects the partitioner from the document it is connected to. Disconnect indicates the end of the usage of the receiver as partitioner of the connected document. Thus, resources the partitioner needed to be operation for its connected document should be deallocated.

The caller of this method should also must ensure that this partitioner is no longer the document's partitioner.

May be extended by subclasses.

Specified by:

disconnect in interface IDocumentPartitioner

documentAboutToBeChanged

public void documentAboutToBeChanged(DocumentEvent e)

Informs about a forthcoming document change. Will be called by the connected document and is not intended to be used by clients other than the connected document.

May be extended by subclasses.

Specified by:

documentAboutToBeChanged in interface IDocumentPartitioner

Parameters:

e - the event describing the forthcoming change

documentChanged

public final boolean documentChanged(DocumentEvent e)

Description copied from interface: IDocumentPartitioner

The document has been changed. The partitioner updates the document's partitioning and returns whether the structure of the document partitioning has been changed, i.e. whether partitions have been added or removed. Will be called by the connected document and is not intended to be used by clients other than the connected document.

This method has been replaced by IDocumentPartitionerExtension.documentChanged2(DocumentEvent).

Specified by:

documentChanged in interface IDocumentPartitioner

Parameters:

e - the event describing the document change

Returns:

true if partitioning changed

documentChanged2

public IRegion documentChanged2(DocumentEvent e)

The document has been changed. The partitioner updates the document's partitioning and returns the minimal region that comprises all partition changes caused in response to the given document event. This method returns null if the partitioning did not change.

Will be called by the connected document and is not intended to be used by clients other than the connected document.

Replaces IDocumentPartitioner.documentChanged(DocumentEvent).

May be extended by subclasses.

Specified by:

documentChanged2 in interface IDocumentPartitionerExtension

Parameters:

e - the event describing the document change

Returns:

the region of the document in which the partition type changed or null

findClosestPosition

protected TypedPosition findClosestPosition(int offset)

Returns the position in the partitoner's position category which is close to the given offset. This is, the position has either an offset which is the same as the given offset or an offset which is smaller than the given offset. This method profits from the knowledge that a partitioning is a ordered set of disjoint position.

May be extended or replaced by subclasses.

Parameters:

offset - the offset for which to search the closest position

Returns:

the closest position in the partitioner's category

getContentType

public String getContentType(int offset)

Returns the content type of the partition containing the given offset in the connected document. There must be a document connected to this partitioner.

Use IDocumentPartitionerExtension2.getContentType(int, boolean) when zero-length partitions are supported. In that case this method is equivalent:

    IDocumentPartitionerExtension2 extension= (IDocumentPartitionerExtension2) partitioner;
    return extension.getContentType(offset, false);
 

May be replaced or extended by subclasses.

Specified by:

getContentType in interface IDocumentPartitioner

Parameters:

offset - the offset in the connected document

Returns:

the content type of the offset's partition

getPartition

public ITypedRegion getPartition(int offset)

Returns the partition containing the given offset of the connected document. There must be a document connected to this partitioner.

Use IDocumentPartitionerExtension2.getPartition(int, boolean) when zero-length partitions are supported. In that case this method is equivalent:

    IDocumentPartitionerExtension2 extension= (IDocumentPartitionerExtension2) partitioner;
    return extension.getPartition(offset, false);
 

May be replaced or extended by subclasses.

Specified by:

getPartition in interface IDocumentPartitioner

Parameters:

offset - the offset for which to determine the partition

Returns:

the partition containing the offset

computePartitioning

public final ITypedRegion[] computePartitioning(int offset,
                                                int length)

Description copied from interface: IDocumentPartitioner

Returns the partitioning of the given range of the connected document. There must be a document connected to this partitioner.

Use IDocumentPartitionerExtension2.computePartitioning(int, int, boolean) when zero-length partitions are supported. In that case this method is equivalent:

    IDocumentPartitionerExtension2 extension= (IDocumentPartitionerExtension2) partitioner;
    return extension.computePartitioning(offset, length, false);
 

Specified by:

computePartitioning in interface IDocumentPartitioner

Parameters:

offset - the offset of the range of interest

length - the length of the range of interest

Returns:

the partitioning of the range

getLegalContentTypes

public String[] getLegalContentTypes()

Returns the set of all legal content types of this partitioner. I.e. any result delivered by this partitioner may not contain a content type which would not be included in this method's result.

May be replaced or extended by subclasses.

Specified by:

getLegalContentTypes in interface IDocumentPartitioner

Returns:

the set of legal content types

isSupportedContentType

protected boolean isSupportedContentType(String contentType)

Returns whether the given type is one of the legal content types.

May be extended by subclasses.

Parameters:

contentType - the content type to check

Returns:

true if the content type is a legal content type

getTokenContentType

protected String getTokenContentType(IToken token)

Returns a content type encoded in the given token. If the token's data is not null and a string it is assumed that it is the encoded content type.

May be replaced or extended by subclasses.

Parameters:

token - the token whose content type is to be determined

Returns:

the token's content type

getContentType

public String getContentType(int offset,
                             boolean preferOpenPartitions)

Returns the content type of the partition containing the given offset in the connected document. There must be a document connected to this partitioner.

If preferOpenPartitions is true, precedence is given to an open partition ending at offset over a delimited partition starting at offset.

This method replaces IDocumentPartitioner.getContentType(int)and behaves like it when prepreferOpenPartitions is false, i.e. precedence is always given to the partition that does not end at offset.

May be replaced or extended by subclasses.

Specified by:

getContentType in interface IDocumentPartitionerExtension2

Parameters:

offset - the offset in the connected document

preferOpenPartitions - true if precedence should be given to a open partition ending at offset over a delimited partition starting at offset

Returns:

the content type of the offset's partition

getPartition

public ITypedRegion getPartition(int offset,
                                 boolean preferOpenPartitions)

Returns the partition containing the given offset of the connected document. There must be a document connected to this partitioner.

If preferOpenPartitions is true, precedence is given to an open partition ending at offset over a delimited partition starting at offset.

This method replaces IDocumentPartitioner.getPartition(int)and behaves like it when is false , i.e. precedence is always given to the partition that does not end at offset.

May be replaced or extended by subclasses.

Specified by:

getPartition in interface IDocumentPartitionerExtension2

Parameters:

offset - the offset for which to determine the partition

preferOpenPartitions - true if precedence should be given to a open partition ending at offset over a delimited partition starting at offset

Returns:

the partition containing the offset

computePartitioning

public ITypedRegion[] computePartitioning(int offset,
                                          int length,
                                          boolean includeZeroLengthPartitions)

Returns the partitioning of the given range of the connected document. There must be a document connected to this partitioner.

If includeZeroLengthPartitions is true, a zero-length partition of an open partition type (usually the default partition) is included between two delimited partitions. If it is false, no zero-length partitions are included.

This method replaces IDocumentPartitioner.computePartitioning(int, int)and behaves like it when includeZeroLengthPartitions is false.

May be replaced or extended by subclasses.

Specified by:

computePartitioning in interface IDocumentPartitionerExtension2

Parameters:

offset - the offset of the range of interest

length - the length of the range of interest

includeZeroLengthPartitions - true if zero-length partitions should be returned as part of the computed partitioning

Returns:

the partitioning of the range

startRewriteSession

public void startRewriteSession(DocumentRewriteSession session)
                         throws IllegalStateException

Description copied from interface: IDocumentPartitionerExtension3

Tells the document partitioner that a rewrite session started. A rewrite session is a sequence of replace operations that form a semantic unit. The document partitioner is allowed to use that information for internal optimization.

Specified by:

startRewriteSession in interface IDocumentPartitionerExtension3

Parameters:

session - the rewrite session

Throws:

IllegalStateException - in case there is already an active rewrite session

stopRewriteSession

public void stopRewriteSession(DocumentRewriteSession session)

Tells the document partitioner that the rewrite session has finished. This method is only called when startRewriteSession has been called before.

May be extended by subclasses.

Specified by:

stopRewriteSession in interface IDocumentPartitionerExtension3

Parameters:

session - the rewrite session

getActiveRewriteSession

public DocumentRewriteSession getActiveRewriteSession()

Returns the active rewrite session of this document or null.

May be extended by subclasses.

Specified by:

getActiveRewriteSession in interface IDocumentPartitionerExtension3

Returns:

the active rewrite session or null

flushRewriteSession

protected final void flushRewriteSession()

Flushes the active rewrite session.

clearPositionCache

protected final void clearPositionCache()

Clears the position cache. Needs to be called whenever the positions have been updated.

getPositions

protected final Position[] getPositions()
                                 throws BadPositionCategoryException

Returns the partitioners positions.

Returns:

the partitioners positions

Throws:

BadPositionCategoryException - if getting the positions from the document fails